1) Field of the Invention
This invention relates to coating compositions and coating film compositions.
2) Prior Art of the Related Art
Usual exterior coating compositions for the four--and two-wheel vehicles are roughly classified into solid coatings and metallic coatings. The solid coatings are prepared by adding a colored pigment. e.g., copper phthalocyanine pigment, quinacridone pigment, perillene pigment, etc. to a coating film. For the methallic coatings, aluminum or like metal powder or mica pigment is usually used together with the colored pigment noted above for the purpose of providing a sense of brightness.
The coating films formed by using the above solid and metallic coatings are required to have sufficient durability for protecting the base as well as ornamental character (i.e.. aesthetic character). Particularly, recent needs for attaching importance to the peculiarity of vehicles and the like are reflected by strong demands for diversification of coating films with respect to the color, ornamentality (aesthetic property), etc. of the top coat. Particularly, there is a stong demand for coating compositions for forming coating films with quality sense variations.
Titanium dioxide particles which are a typical white pigment, have heretofore been applied to many coating compositions because of excellent whiteness and concealing and weather-proof properties. Also, to meet recent coat color diversification demands there are coat color proposals which use far fine titanium dioxide particles compared to the conventional titanium dioxide particles. However, there is no example of study of variations of the coat color sense with particle shape variations. As a sole exception, titanium dioxide coat mica pigment is a pigment shape variation. This pigment, however, is mainly composed of mica, and therefore its coating films inevitably have reduced hiding property and color attachment power. In addition, in shelf time it sinks greatly because its particle diameter and weight are large.